Eq.(REF ) has two possible forms of solution. The first form
is found using result 254.00 in [1]}. Its parametric form is
\( \left\lbrace  {\begin{array}{l}\varphi = \frac{\textstyle \varphi _2-\varphi _1 n \mathrm {sn}^2(w|m) }{\textstyle 1-n \mathrm {sn}^2(w|m)} ,\\\xi = \frac{\displaystyle 1}{\displaystyle \varepsilon p}(w\varphi _1+(\varphi _2-\varphi _1)\Pi (n;w|m)),\\\end{array}} \right.\) 
